Many times it becomes necessary to dispense a precise stream of fluid to narrowly confined cavities. One example of this is in the application of water, medicine solutions, air, and the like to root canals and especially the apical foramen region of root canals. The prior art includes assemblies which directly connect, i.e. without the use of an adapter, a common needle apparatus of the type having a hollow needle and a hollow hub or needle-carrying member with a flange to a common hypodermic syringe of the type having a hollow barrel fitted with a plunger and a LUER-LOK.RTM. (U.S. Reg. No. 306,120) nozzle. These assemblies can be used to provide a precise stream of fluid to a narrowly confined cavity but not without problems. Examples of this prior art can be found in U.S. Pat. Nos. 3,745,655 and 3,949,748. The hypodermic syringe used in these assemblies requires the user to manually move the plunger to dispense the fluid. In addition, the hypodermic syringe used in these assemblies provide a very limited source of fluid requiring frequent refilling of the syringe barrel. It thus becomes desirous to use a fluid dispensing system which utilizes a source of fluid under continuous pressure and a dispensing head of the type having an outlet and a valve to terminate the flow of the fluid through the outlet. However, the outlet of the dispensing head of these systems are not designed to directly connect to a LUER-LOK.RTM. type needle. Instead, the outlet is usually designed to connect to a non-disposal and normally larger dispensing attachment not capable of accessing narrowly confined cavities, such as root canals.
The applicant is aware of adapters/connectors which connect LUER-LOK.RTM. type needles to rubber or plastic tubing as illustrated on page 1497 of the THOMAS SCIENTIFIC.RTM. 1988-89 catalog or on page 294 of Sigma-Aldrich Techware. However, these adapters/connectors cannot connect a LUER-LOK.RTM. type needle to a fluid dispensing instrument capable of providing fluid under continuous pressure. Thus, the object of the present invention is to connect a LUER-LOK.RTM. type needle to the outlet of a fluid dispensing instrument of the type capable of providing a fluid under continuous pressure to thereby enable a user to provide a precise stream of fluid to a narrowly confined cavity.